The invention relates to a flexible shipping container, particularly for bulk material, whose carrying bag consists of a bottom, at least one side wall, and a top wall and that is made of a flat-shaped article.
Such shipping containers that are typically made of synthetic fibers or of small synthetic bands and that include carrying loops as well as a fill and a discharge opening are used for purposes of transporting bulk material and are stored next to one another or on top of one another in a storage room by using a fork lift truck. To utilize the storage room to its full capacity, the dimensions of the shipping container are usually adapted to the interior dimensions of the storage space, e.g., a 20-foot container.
If the shipping container is lifted onto the storage surface or onto a shipping container that is already stored in the storage space by a fork lift, which has a lifting frame that has a sufficient support area, then, as is already known, the shipping container can be placed on a thin sheet that has been placed loosely onto the support area of the lifting frame. This achieves that the conventional pallets are no longer needed and that the load consisting of filled shipping containers can be stored more densely. In loading, one not only saves the bottom pallet but in stacking also the top pallet. The disadvantage is that the sheet that is positioned under the shipping container and that is known as a slip sheet does not have a good connection with the bottom of the shipping container and that the shipping container can slip off the sheet during manipulation with the lifting frame. An additional disadvantage is that additional handling steps are required for placing the sheet, such that another person is required for-loading in addition to the fork lift operator.
It is, therefore, a principal objective of the present invention to construct a shipping container of the type mentioned above that is better suited for loading with a fork lift, in particular for storage without pallets in a transport container, and where the expenditure of human labor during loading can be reduced, and where especially the disadvantages of slip sheets do not occur.
According to the invention, this objective is achieved in that the carrying bag of a shipping container includes at least one pocket or flap located at the bottom of the carrying bag such that a stiffening object can be placed between the bottom and the pocket or flap. The European Patent No. EP 0 084 942 A1 discloses a bulk material container having a pair of slings, which is opened and closed by a slide valve gate having handles at the opposed ends, and an off-center opening adapted to be placed into full or partial registration with the opening in the bottom wall of the container to control the flow of bulk material from the container. The known valve plate may stiffen the bottom of the container. However, there is no bag or pocket to hold a special stiffening plate as proposed with the invention.
The pocket or flap is created, according to the invention, by attaching at least one material section to the bottom of the carrying bag. Preferably, the pocket is made of the same material as the remaining part of the carrying bag.
Typically, the shipping containers are made of a high-strength fabric or knit of polymer strings, or small synthetic bands or of paper or synthetic foil.
If only one material section, that is, a flap is connected to the bottom, a simple pocket is created that can also be called a double bottom. The pocket exhibits a longitudinal opening in the area of one bottom edge of the carrying bag.
In a stronger design, for example, two material sections on top of one another may be connected to the bottom with three side seams forming a pocket.
It is possible to arrange two pockets next to one another in the bottom area of the carrying bag, with the pocket openings pointing to the outside.
Both the single and the double or multi-layer material section can project beyond the bottom edge and end in a free flap or pocket section that can be turned over at the edge and can be fastened in a detachable manner to the side wall of the carrying bag using suitable closures such as Velcro-type fasteners.
It is advantageous to connect the projecting pocket or flap section to the side wall with at least one flexible band, string or the like that can be used to keep the pocket or flap section in a slightly slanted position to the bottom plane when in the folded up position. During production of the carrying bag, the projecting pocket or flap section can be made of the material of the bottom as its extension. The pocket or flap can be stiffened through appropriate folding of the material (one or multi-layer).
The main purpose of the pocket that is attached to the bottom of the carrying bag is to replace the so-called slip sheet that is used to aid in pushing or pulling the filled shipping container, which is placed on the special front end of the fork lift.
The invention also relates to a shipping container equipped with such a sheet that is located in the pocket. It is preferable that after inserting the flat object, the pocket projects beyond the bottom edge of the carrying bag. In this manner, the projection can be grabbed by the fork lift and moved together with the shipping container.
The flat object can be made of sheet metal, a synthetic plate, laminated or wood material, cardboard or of textile materials. It is possible to provide the flat object with perforations (as in a perforated sheet). Preferably, the flat object is slightly bent or crimped.
The shipping container subject to the invention contributes to an about 10 to 20% increase in the storage capacity of a 20-foot container and to the fact that fewer people are required for loading. Furthermore, for a typical 20-foot container, the use of 20 to 40 pallets can be avoided. This results in lower shipping costs per weight unit and savings for pallet material (wood) and fuel. This saves natural resources and puts less stress on the environment.
The idea of the invention does not only relate to cube-shaped containers but also to cylindrical or prismatic ones. Further, the invention also relates to shipping containers made of high-strength synthetic foil, or textile materials such as linen, or of paper with one or two walls.
For a full understanding of the present invention, reference should now be made to the following detailed description of the preferred embodiments of the invention as illustrated in the accompanying drawings.